1. Field of the Invention
The present invention pertains to a split-diode technology high-voltage transformer, especially for a trichromatic cathode tube.
2. Description of the Prior Art
In a split-diode technology high-voltage transformer, i.e. a transformer of the secondary winding type comprising two or more sections separated by diodes, a tap is made on the middle point of one of the sections to draw off the voltage needed to supply the pre-focusing grids of the cathode tube, the anode of which is powered by the extra-high voltage of the transformer.
However, this voltage drawn off at the middle point is a ripple voltage, the voltages at the terminals of the two half-windings of this section being disymmetrical owing to the existence of various stray capacitances which affect these two half-windings.
To reduce this ripple, an additional capacitor can be mounted in parallel on the winding which displays the weakest stray capacitance in such a way as to symmetrize the wave forms produced by the two half-windings, but a method of this type is not valid for mass production since it is generally necessary to adjust the value of the additional capacitor to each transformer, for the stray capacitances of the transformers from one and the same production batch are not constant.